Motion-picture apparatus.



C. F. JENKINS.

MOTION PICTURE APPARATUS.

APPLICATION FILED JAN. 8, 1912.

1,091,343. I Patented Mar. 24, 1914 2 SHEETS-SHEET 1.

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c. F. JENKINS.

MOTION PICTURE APPARATUS.

APPLICATION FILED 1411.8, 1912.

1 091 343 Patented Mar. 24, 1914.

2 SHEETS-SHEET 2.

HWIIIIIHH awvemlioz Mia aw" 1 4 the tube .i by a guide UNITED STATESPATENT OFFICE.

MOTION-PICTURE APPARATUS.

Specification of Letters Patent. Patented Mar. 24, 1914-.

Application filed January 8, 1912. Serial No. 669,998.

To all whom it may concern: I

Be it known that I, CHARLES FRANCIS JENKINS, a citizen of the UnitedStates, residing at Washington, in theDistrict of Columbia, haveinvented certain new and useful Improvements in Motion-PictureApparatus, of which the following is a specification, reference beinghad therein to the accompanying drawing.

The object of this invention is to provide a simple motion picturecamera that shall be unusually accurate in operation, locating thepictures with precision, and not materially affected in accuracy by anywear of the parts. These ends are attained by fixing the distance of thefilm from the lens at the time of exposure and then moving the lens andfilm together along the line of the axis of the lens ,or perpendicularlyto the plane of that portion of the film in position for exposure. Thefilm is fed transversely to the axis of the lens, at proper times bynovel and advantageous means.

In the accompanying drawings, Figure 1 is a front elevation of a portionof a camera embodying the invention. Fig. 2 is an elevation, lookingfrom the right in Fig. 1. Fig. 3 is a plan view of the same devices.Fig. 4 shows in elevation'the-rear face of a film-pressing plate.

In these figures, A represents a camera box, "A, A transverse partitionstherein, and B, B film receptacles within the box. Upon fixed rods orways, C, in the front portion of the box is mounted a rigid frame C towhich are rigidly'attached a lens tube D, sliding in a felt linedaperture in front of the box, and an alining tube D which in like mannermoves back and forth in a corresponding opening in the partition A.Between the tubes D, D lies a shutter E which is rotated at proper speedby devices not shown. in the rear of the partition A is mounted asprocket drum F actuated by a shaft F to draw film G from the receptacleB and to return it after exposure to the receptacle B, the outgoingportion of the film held against theupper side of the by a spring F thereturning portion being pressed against the iower side by a liiredevice. The in its course passes around small rollers H, H, H H is heldagaii the end face of lbs, and

screws are flattened as seen in Fig. 4 and the plate is provided withlots I so formed that the plate is readily lifted and detached from theposition indicated in that figure. The shaft F bears a gear, J, meshingwith a pinion J upon a shaft J 2 which carries a crank-plate K connectedby a pitman K to the frame C carrying the lens tube and the tube D,-which are thus caused to move back itnd' forth along the line of theaxis of the ens.

being properly proportioned, that when the shaft isjrotated uniformly,the film will be continuously advanced by the drum and will be fedintermittently past the end of the tube D, and further. that it will beexposed at a moment when it is at rest as to longitudinal advance, theshutter'opening then alining with the two tubes. The film feeding partsbeing in the positions indicated in Fig. 2, rotation of the shaft F,gear J and drum F will obviously tend to increase the slack above theplate I and to draw the film, to an equal extent, from the lower side ofthat plate, but a slight rotation of the gear causes a half rotation ofthe crank-plate and carries the frame, tubes and plate forward quicklyyet with gradually increasing and similarly decreasing speed, theforward movement being barely more than enough to bring the film againstthe plate A and to cause the springs to yield slightly thereby arrestingthe film atthe end of each. feeding stroke when it is at exactly apredetermined distance from the sprocket drum, thus insuring desirableac curacy in feeding at high speed. As the film cannot be drawn from thelower side of the drum, this forward movement pulls down from the slackabove a length of film substantially equal to the distance through whichthe tubes move plus the length of film fed rearward by the drum duringthis short interval. The plate and the other parts now move in thecontrary direction and the rate quickly exceeds the rate of the periodthere is no slipping movement or ed movement of the film under the platethe lens, and the parts this moment the r exposes the when the screwsare given a quarter turn- It follows from the construction, the parts fed by drum and hence for a short tive displacement whatever until afterthe shutter terminates the exposure.

It is obvious that the distance of the lens from the subject beingphotographed varies as the lens is carried back and forth, but thedistance of the subject from the lens is ordinarily so great,relatively, that'this variation is negligible or has no appreciableeffect. It is also evident that the construction avoids independent orseparate movements which must be accurately coordinated, that mountingall moving parts upon mutually supporting plates or partitions at rightangles to each other and extending across the casing gives verydesirable rigidity and allows using in extremely small spacethd'sllllttel behind the lens and the single sprocket drum for bothfeeds, that few gears are employed, and that ordinary wear of thereciprocating parts or the parts causing reciprocation has no effectupon the feed.

l/Vhat I claim is: I

1. The combination with a closed'casing having a rigid transversediaphragm, of a lens tube arranged for sliding longitudinally in an Iaperture in said casing, an alining film guide tube arranged for slidingsimi rly in an aperture in said diaphragm, means for re-; ciprocatingthe two tubes together, means for yieldingly holding a transverse filmstrip at the rear end of the guide tube, and means for holding thatportion of the strip which has passed the guide tube against the pull ofthe latter in its forward movements; whereby the film is advanced withrespect to the guide tube during each forward move ment of the latter.

2. The combination with a closed casing internally divided bya fixedtransverse diaphragm, of a lens tube and a connected alining film guidetube arranged to fit and slide in apertures in the casing and diaphragm,respectively, a shutter arranged for rotation between said tubes, meansfor axially reciprocating the two tubes, means for yieldingly holding afilm strip against the inner end of the guide tube, means for dimeans totake up recting film to said holding means, and means for feeding filmfrom said holding slack due to rearward movement of the guide tube andfor holding this portion of the film against the pull thereon when theguide tube moves forward.

3. The combination with a lens reciprocating in its own axial line, of afilm guide reciprocating with the lens and arran ed for yieldingslightly when, in moving or- Ward, it meets strong resistance, and meansfor positively and uniformly arresting the forward movement of the guideslightly before it reaches the limit to which it would otherwiseadvance, whereby the guide and film therein always move forward to thesame point, precisely, irrespective of ordinary wear of arts causingreciprocation.

4. The com ination with a casing of a lens tube fitting in an aperturein the casing, a film guide tube alining with the lens tube, at somedistance in the rear thereof and rigidly connected thereto, means forreciprocating said tubes, means whereby such reciprocation causes filmto pass intermittent-1y across the inner end of the guide tube, and anupwardly detachable late springpressed on each side against t e innerend of the guide tube.-

5. The combination of a lens and film guide reciprocating together inthe axial line of the lens, means for frictionally holding in said guidea film strip transverse to said line, and means for taking up at oneside of said guide the slack in the film due to rearward movement of thelatter and holding the same portion of the film against contrarymovement while the guide moves forward; whereby each forward movement ofthe guide causes the film to slip therein, presenting a fresh portion insaid axial line.

In testimony whereof I afiix my signature in presence of two witnesses.

ROBERT CRAIG GREENE, James L. Cmwronn.

